Provider-Internal Aggregation based on Geographyto
Support Multihoming in IPv6

Features:

No new protocols

No new code

No new hardware

Scales to around 5 - 25 million multihomers

May be compatible with longer-term solutions

But:

IPv6 address allocation must change fundamentally

More complexity in provider networks

Needs some level (but not full!) of interconnection

First picture:

A simple internet with two ASes: black and white, that are each present in
four geographic regions and interconnect in each region.

Second picture:

Some customers. The color represents the PA address blocks the customer has
addresses from.

Third picture:

When the white AS in the south wants to send traffic to some customers of the
black AS it routes the packets as per the PA aggregate. This means the traffic
ends up at the black AS at the nearest interconnect point.

Fourth picture:

The routing table for the west router for the white AS: aggregate routes for
address blocks from the other AS, more specifics for the white AS its own
customers.

Fifth picture:

With geographical addressing the address block depends on location and is
shared between ISPs.

Sixth picture:

Now the white AS first routes the traffic to the right location within its
own network and only then turns it over to the destination AS.

Seventh picture:

In the routing table there is now also a more specific route for the black
AS's west customer and aggregate routes for other geographic regions.

Read the drafts, these explain it much better. If you still have questions,
email me at iljitsch@bgpexpert.com.